At three weeks, chicks suddenly walk on their “knuckles” with their toes curled under. Or layers on good feed lay thin-shelled eggs. The owner switches suppliers, adds chalk, buys an antibiotic — and the real problem is a few grams per tonne that never made it into the feed. Vitamins and trace minerals are less than one percent of the ration, but without them the other 99% doesn’t work.
What a premix is and why you need it
A premix is a blend of vitamins and trace minerals (manganese, zinc, copper, iron, iodine, selenium), sometimes with amino acids, on a carrier. Commercial compound feed already contains it. If you mix your own, a premix is a must: usually 0.5–1% of the feed by weight, with the exact rate on the label.
- Match species and age. Broiler, layer, pullet and breeder premixes are different. A layer premix in broiler feed means too little of some vitamins and too much calcium.
- Not by eye. A half-percent rate means 5 kg per tonne or 50 grams per 10 kg. You can’t measure that without scales.
- Mix in two steps. First blend the premix with a small portion of feed, then mix that portion into the rest. Otherwise some birds get a double dose and others none.
Signs of deficiency
In young birds
| What you see | What’s missing |
|---|---|
| Falls over, twists its head back, walks in circles — usually at 2–4 weeks | Vitamin E and selenium |
| Walks on its “knuckles,” toes curled under | Vitamin B₂ |
| Swollen hock, leg twists out to the side | Manganese, choline, niacin |
| Scabs on the feet and at the corners of the beak | Biotin |
| Rubbery bones and beak | Vitamin D₃ |
In layers
| What you see | What’s missing |
|---|---|
| Thin and soft shells | Vitamin D₃ |
| Discharge from eyes and nostrils, white spots in the mouth | Vitamin A |
| Fewer eggs, pale yolks | Vitamin A |
| Plenty of eggs, but chicks hatch poorly | Vitamin B₂ and other B vitamins |
Shortages show up most often on homemade feed without premix, on old feed, and in birds kept without sunlight or greens.
Paralysis also comes with Marek’s disease, stargazing with Newcastle, and leg problems in broilers with fast growth. If several birds show signs, take them to a vet: a necropsy of a dead bird tells you more than any table.
Vitamins in the water — when it works
Water-soluble vitamin packs are good as a short course: after vaccination, transport, a heat wave, illness, at the start of molt. Three to five days per the label — and back to normal feed. They won’t fix a constant shortfall in the ration: vitamins break down quickly in water, and birds don’t drink evenly.
- mix a day’s worth, not a week’s;
- in metal drinkers in the sun, vitamins break down even faster;
- flush the drinkers after the course: sweet water feeds bacteria.
Vitamins go off too
A bag of premix in a warm shed loses a noticeable share of its vitamins A, D₃ and E over one summer. Compound feed after a couple of months of storage is no longer what the label says either.
- Buy premix for 2–3 months, not a year.
- Keep it cool and dark, with the bag closed.
- Don’t pre-mix premix with limestone and salt: vitamins break down faster in the blend.
- Finished feed — no longer than 3–4 weeks.
More isn’t better
Too much vitamin D₃ deposits calcium in the kidneys, too much vitamin A interferes with other vitamins, excess selenium is toxic. A double dose of premix “just in case” is wasted money at best. If you feed commercial compound feed, you don’t need a separate premix.
Supplements in your records
In EggPulse premixes and additives go into the feed store as ingredients, and the recipe sets their share. When you feed by recipe, the premix is written off along with grain and meal, so you can see how much is left. How to put the whole mix together is in the article on rations from your own grain.
